Dual Link RGB 4:4:4 editing with FCP

[Emery]

I think most people who cut 4:4:4 in FCP create a cuts only EDL and finnish in shake or After Effects. And now with FCP 5 and Shake 4 this should be a snap, you can export your project to shake and finnish in that.

Emery

[Emery]

“Back to topic…. I thought FCP supported up to 32 bit FP? The engine renders at 32 bit but writes only 8 bit? ”

Yes what is up with that? If its calculating in 32bit float when set to high precision YUV, than why do you end up with an 8bit file in a 10bit wrapper?

[Francois Stark]

From FCP 4; in the timeline settings (command-0):

When you are on a 10 bit timeline you can choose whether you want effects rendered in RGB 8 bit, YUV 8 Bit, YUV 10 bit or 32 bit floating point precision. After rendering it gets rounded off to the precision of your timeline.

Regards
Francois

[Christopher Tay]

Francois,

So to keep things less complicated, if one wants to use FCP as a finishing system in 10bit RGB 4:4:4, it is possible as long as we set the rendering to 32bit float ?

-chrispy

[Francois Stark]

That’s what apple says. I don’t have the tools to test it, but have found two issues regarding rendering accuracy:

-when using Joe’s filters color glow, I get banding on 8 bit YUV setting, but 10 bit YUV then banding is gone, even when it is a DV timeline!!!

-when combining two filters – I think it was joe’ glow and 3 way CC, I switched to floating point rendering, and got some rendering errors on the visual highlights. Like the numbers “punched through” the brightest levels and replaced it with darker values.

I just changed the timeline to 10 bit rendering and rerendered. Problem gone.

Regards
Francois

[Kaspar Kallas]

In RGB mode all renders are 8 bit only in FCP 4.5 (heard a rumor and waiting for my copy but in FCP 5 RGB gets converted to YUV then rendered then converted back to RGB for 10bit support – I even don’t rembeber did I read this somewhere or I saw in my sleep so …. you know what it worth)
In YUV 4:2:2 there is no problem with 10bit
That is also why why avid has no problem with 10 bit in newer systems because we are dealing with YUV data in 4:2:2 and there is no way to use 4:4:4 because no dual SDI input

-Kaspar

[Gary Adcock]

[Emery] “”Back to topic…. I thought FCP supported up to 32 bit FP? The engine renders at 32 bit but writes only 8 bit? “”

Emery let’s be a bit more specific, you are correct that some of the effects in FCP only render in 8bit, even when your timeline is set for 10bit.
This is the same for the comparable avid products. Setting the correct bit depth is a function of the operator as well as the software. Understand that working Dual Link is not for the timid and almost requires that the operator have either the knowledge base to handle the process or hire one of the less than a dozen or so people that are familiar working with 4:4:4 in FCP.

did some one mention that FCP does not see RGB files and converts the video to YUV for Playout? or that the files you will be working with exceed 250mgs a second and can reach nearly 500mgs a second with certain versions of the format?

or that the HDCAM-SR format is ONLY 10bit.. so maybe the 32 bit rant is a little unfounded..

gary adcock

Studio37
HD and Film Consultation